Fluid-pressure air-brake.



W. M. AUSTIN. FLUID PRESSURE AIR BRAKE.

APPLIOATION FILED MAY 18,1904.

w. M. AUSTIN.-

FLUID PRESSURE AIR BRAKE.

APPLICATION FILED MAY1B,1904.

Patented Mar. 23, 1909.

6 SHEETSSHEET 2.

W. M. AUSTIN. FLUID PRESSURE AIR BRAKE. APPLICATION FILED MAY 18,1904.

91 5 3724. ,Patented Mar. 23, 1909.

6 SHEETS-SHEET 3.

Fu/l Ewan'zmksW y v WITNESSES: W W VENTOB I W. M. AUSTIN. FLUID PRESSURE AIR BRAKE. APPLIUATION FILED MAY 18, 1904.

Patefited Mar. 23, 1909.

5 SHEETS-SHEET 4.

M32 E Ill 7 42 I &

INVENTOR Wm 771. M

WITNESSES. M )7 W. M. AUSTIN. FLUID PRESSURE AIR BRAKE. APPLICATION FILED MAY 18,1904.

91 5;? 4cn A I Patented Mar. 23, 1909.

6 BHEETSSHEET 6.

INVENTOR WITNESSES.

fiwu, 1, M

. UNITED STATES PATENT OFFICE.

WALTER MERVILLE AUSTIN, OF SWISSVALE, PENNSYLVANIA, ASSIGNOR TO THE WESTING- HOUSE AIR BRAKE COMPANY. OF PITTSBURG, PENNSYLVANIA, A CQRPORATION OF PENN.

SYLVANIA;

FLUID-PRESSURE AIR-BRAKE.

' Swissvale, in the county of Alleghenyand State of Pennsylvania, have invented certain new and useful Im rovements in Fluid-Pressure Air-Brakes, whichthe following is a full, clear, and exact description.

This invention relates to fluid pressure train brakes, the' objects being to devise a system of brakes suchthat the engineer can ,speed and comes to rest.

have perfect control of the brakes at all times. He may make a graduated application of the brakes or an emer ency application, and he '-1nay release the brakes at will, the same asin the'systems now in use. He can also make a raduated or partial release of the brakes, and when once the brakeshave been a plied, the engineer may be sure that every brake cylinder in the train will have the same pressure maintained therein until the pressure is increased or diminished by a new movement of the brake handle, irrespective of any leakage that may occur in any part of the system. I also provide for a practically instantaneous application of the rakes in caseof emergency, and in cases where the train is operated at high speeds the emergency application furnishes a much higher pressure in the brake cylinder than for ordinary speeds, which pressure is automatically reduced as the train decreases in By my improved system I can keep the product of brakecylinder pressure and the coefficient of friction between brake shoes and wheels approximately at a constant.

in accomplishing the objects of my invention, I use atriplevalve in some respects similar to the one described in. my patent application filed Oc'tl24, 1903, Serial No.

178,339 and an engineer's valve similar in some respects to the engmeers valve de-' scribed in my patent application filed Qc't.

.- 29, 1903, Serial No. 179,043.

One feature of my improvements resides in the use of puppet valves in my triple valve, whereby I amable to materially reduce the. travel of the diaphra ms and thus avoid the undue strain on the iaphragms experienced when slide valves are used. In order to save s ace in the'enginee'rs cab, I have separated t e feed valve and discharge valve from the manually o' erated'portion of the engineers' valve and p acedthern outside the cab. The

Specification of Letters Patent. Application filed. May is, 1904.. Serial No. 208,496.

Patented March 23, 1909.

ing anauxiliary cock We can chan e the 'pressure maintained in the train pipe y the feed valve. from a low ressure to a hi h pressure, or vice versa. f the train is to e run at a low speed, the lower pressure is used, but if the s eed is to be high, the higher pressure is used. In order to prevent sliding of the wheels, as the train decreases in speed and comes to rest, on account of the increase in the coeflicient of friction between brake shoes and wheels, I use a high speed release valve to control the feed valve to admit pressure from main reservoir to trainpipe and thus partially release the brakes after an emergency application at high speed. The'high speed release valve has a centrifugal governor geared to some moving art of the train, preferably to an axle on-the ocomotive. This governor, after an emergency application, regulates the train-pipe pressure according to the speed of the tram at every instant, while a spring automatically closes'the direct exhaust port of the engineers valve. Ineffecting an instantaneous rise in brake cylinder pressure to its full value in emergency applications, I use an automatic valve so designed that when train pipe pressure has about ceased to flowjnto the brake cylinder, 9. large port is opened betwieen the auxiliary reservoir and brake cyl- 1n er.

engineers valve is so designed that by turn- My invention will be described in detail bodying my invention; Fig. 2- is a longitudinal section of my improved triplevalve with parts of the auxiliary reservoir, the supplemental reservoir and the pipe leading to the brake cylinder; Fig. 3 is a part section and part elevation of my improved engineer's valve with train pipe regulator; Fig. 4 is a section on line w.x of Fig. 3; Fig. 5 1s a partial section on line l -41 of Fig. 3 Fig. 6 is 'a plan view of the rotary valve shown in elevation in Fig. 3; Fig. 7 is a Ian of the valve seat shown inelevation in ig. 3; Fig. 8 is a partial section on line z-z of Fig. 7, showing the cockfor changing from low to high train pipe pressure and vice versa; Fig. 9 is a longitudinal section of the combined equalizing feed valve and equalizing discharge valve; Figs. 10 and' 1 1 are respectivelysections of the use upper and lower parts of my automatic high speed releasing valve; Fig. 12 is a modificatlon of part of the mechanism shown in Fig.

10; Fig. 13 is a modification of art of the.

mechanism shown in Fig. 3, and ig. 14 is a diagram of the passages connecting rotary valve with train pipe regulator.

'In the following description stress will be laid only upon such parts of the construction as concern the present invention, it being understood that numerous features found in ordinary fluid ressure brakes are used in con,- junction wit the novel devices.

Referring to the drawings, 1 is a pipe leading from the main reservoir or other source of fluid pressure. Connection is made through 2 with the supply port of the engineers valve 5 and through 3 with the equalizing feed valve 6 andthrough 4 with the high speed releasing valve 7. Pipe 8 connects the high speed releasing valve 7 with the engineers valve 5. Pipe 9 connects the common equalizing chamber of the equalizin feed valve and the equalizing discharge va ve with the train-pipe regulator of the engineers valve. Pipe 10 isa branch from train-pipe 11 to engineers valve.

12 is the equalizing discharge valve, 13 is the triple valve connected to a branch of the train-pi e 11, and to the auxiliary reservoir 14 and brake cylinder 15 in the usual manner, and also connected to the supplemental or pressure reservoir 16. The levers, rods, beams and shoes connect to thebrake cylinder in any approved manner.

, My triple valve is contained in a case havingfour sections; between thesesections are clamped the outer edges of the three diahragms 17, 18 and 19. The space 20 to the eftof the diaphragm 17 is in communication with train-pipe 11 which is connectedto the triple valve at 21. The space 22 between diaphragms 17 and 18 connects with brake cylinder 15 through passage 23. The space 24 between diaphragms 18 and 19 is open to atmosphere through a port 24*. The space to the right of diaphragm 19 is in direct communication with supplemental reservoir 16 which projects into the auxiliary reservoir 14. Check valve 25 normally closes a passage 26 leading from space 20 to auxiliary reservoir 14. In the cut away portion a check valve similar to 25 normally closes a passage leading from space 20 to supplemental reservoir 16. The middle of diaphragms 17, 18 and 19 are clamped between disks 27 and 28 and separators 29 and 30. Puppet valve 31 normally closes passage 32 between space 24 and passage 23. Puppet valve 33 normally closes passage 34 between space 22 and passage 26. Valve 35 normally closes passage 36 also between space 22 and passage 26. The valve is formed with a pair of valve surfaces 39 and 39 adapted to engage separate valve seats in such a way that the a surface 39 is held against its seat by the train pipe pressure, while the surface 39 is constrained awayifromits seat by the pressure in the brake cylinder. The ports 36 into the auxiliary reservoir are located atan intermediate point of the valve, so that the ressure 'of the auxiliary reservoir is balance on the two end surfaces of the valve. In practice it is not quite balanced, there being a slight excess pressure on the surface 39. By reason of this construction, when the brake cylinder pressure becomes equal to that of the train pipe, the valve 35 is thrown to the left until 1ts6 surface 39 contacts with the sealing leather 38. This opens the intermediate ports 36 leading to the auxiliary reservoir directl into the brake cylinder. Space 40 to the left of' piston 37 is open to space 20 through port 41.

The emergency valve 42 and the emergency check valve 43 are the same as those shown in my 1903, previous y referrer to.

The engineers'valve consists of a rotary valve 47 and a pressure regulator 48. 48 automatically controls the pressure in the equalizing chamber 98 (Fig. 9). valve has two large ports or cavities 49 and 50 connected by a passage 51 and two small orts 52 and 53 connected by a passage 54.

otary valve 47 rests on valve seat 55. 55 is provided with port 56 leading to the train pipe, port 57 leading to the main reservoir through pipe 2, port 58 leading to the atmosphere at 58*, port 59 leading to the equalizing chamber 98, through pipe 9, port 60 loading to cock 61, and when handle62 of cock- 61 is in position shown in Fig. 3, which is the position for high speed, port 60 leads through port 63 in cock key 64, thence through port 65 to pipe 8 leading to high speed release valve 7. When handle 62 is moved so that it is pointing outward from the plane of the drawmg, Fig. 3, all communication between port 60 and high speed release valve 7 is cut olf. Rotary valve seat also has a groove 66 communicating with port 56 and thence with train pipe, and a groove 67 connected by port 68 with cock 61. When cock handle is 1n position shown in Fig. 3, port 68 is cut oil, but passage is connected with port 69 and space between diaphragms 71 and .72 is 0 011 to atmosphere through port a, but when handle 62 is turned so that it points outward from the plane of the drawing, port 68 communicates through port 69 in cock key 64 with passage 70 and space between diahragms 71 and 72 of the ressure regulator. 1roove 67 also connects liy passage 73 (in the cut away portion of Fig. 3) see Fig. 14, with space 74 to the right hand of diaphragm 72. Passage 75 connects from main reservoir through port 57 to space 76 to the right hand of valve 7 7, by handle 78 through valve stem 79. Suratent ap lication of Oct. 24, I

The rotary Rotary valve 47 is turned.

sition shown in Fig. 3a

tion, allows s ring 84 to expan rounding 79 and turning with it is a cam 80. Inside cam 80 is as ring'81 fastened to the cam at one end and aving a hook at the free end adapted to enga ea projection 82 on a non-movable\part o the apparatus when handle 78 has been turned to high speed release position and to distort spring 81 while handle is moving from high speed release to emergency position. Spring 81 will return rotary valve 47 and handle 78 from emergency osition to'high speed releasing position, w en the manual pressure is removed from handle ,78. The slidingspring abutment 83 resses against cam .80; "A movement of rake handle from running position toward full equalized pressure posiand rec nose the pressure t at it can exert on spring-head 85; S ring 86 is held in compression by the adjusting plug 87 and jani nut 88. Dia hragms Hand 72 are clamped in'the center between spring-head 85, ring 89 and'ca 90, and at. the circumference are clamp between shell-91, ring 92 and head 93. Now diaphragm 71 is of larger area than diaphragm72, so when 000 handle 62- is in p0- space between-71 and 72 isopen to atmos herethrough'passage 70 and ports 69 an a, and equalizing chamber-is in communication with space 74 only, a much larger pressure is required to, balance sp'rings84 and-86 than wheneq'ualizing chamber pressure'is on both sides of diaphragm 72. Valve 95 normally closes port 96 leadingfrom space 74 to atmosphere.

- A movement of diaphragms=71 and 72 to the left, brings valve 95 against abutment-97 and opens space 74 to'atmosphere, while a stem 110 held down .by spring 111.

movement of diaphragms'll and 72'to the right pushes open valve 77 and admits pressure from main reservoir to space 74.

In the modification; Fig. 13, the action of the parts are the same as in Fig. 3, and the corresponding" parts are indicated by the same reference characters.

0n opposite sides of equalizing chamber 98 (Fig; 9)far'e pistons 99 controlling valve 100 which normally closes port-101 leading from train-pipe to the atmosphere, and 102 controlling valves 103 and" 104 which normally close ports leading from main reservoir to'train'p'ipe throughpassag'ef105.

- 106 is an axle on the locomotive to which is fastened the gear 10.7 in mesh with pinion 108. Pinion 108 turns in bearing 109. In-- side of pinion-108 and turning with it, a

astened-to stem 110 is the centrifugal ball governor'112. The upper endof 112 swivels on ste n'1-113. The center of diaphragm 114 is clamped between. stem 113Tand cap115 while circumference of 114 isclamped between shell 116 and head 117. Pressing-upward on stem 113 is spring 118 held in com-' 120. Port 121 connects from main reservoir through .pipe 4 to space 122 above valve 123.-'Space 124 above diaphragm 1 14 connects with cock 61 of enginecrs valve through pipe 8. A downward movement of diaphragm 114 brings valve 125 against abutment 127 and lifts valve 125 oil its seat, opening space 124 to atmosphere,

from main reservoir to space 124. In the modification, Fig. 12, the action of corresponding parts are indicated by the same reference characters. 1

' The operation isas follows. Assuming 'that thecock handle 62 has been ,turned to aposition at right angles to, that shown in Fig. 3, that train-pipe, auxiliary reservoirs and supplemental reservoirs have been charged to the full running ressure for ordinary speeds and that bra e handle 78 is standing at, running osition, to make a service application 0 the brakes, brake handle is moved to a service position, the degree of movement depending on the reduction of train pipe pressure desired. This movement of handle 78 has brought apart of cam 80 of smaller radius opposite spring abutment 83, allowing 83 to move to the left under pressure of spring 84 'and reducing the pressure of said spring on diaphragms 71'. and 72. This movement of the valve has also brought port 52 over groove 67. The pressures to the right of 71 and 72 push them forward ,opening valve95 and allowing pressure in equalizing chamber 98 to escape through pipe 9,ports 59, '53, 54 and 5,2, "groove 67, passage 73, space 74 and port 96 to atmosphere, (pressure also escapes sage 7.0, 69, 68, groove 67, 73, etc. to atmosphere at 96) until equilibrium is established etween the forces on diaphragms 71 and 72, when valve 95 will close. Train-pipe pressure to the left hand of piston 99 will overcome; the reduced pressure in e ualizing chamber 98 and move piston 99 to t e right, opening valve 100 and allowing pressure to escape from train-pipe 11 to atmosphere through port 101 until train-pipe pressure is reduced to a little belovi pressure in chamber'98, when piston 99 will move to the lefthand and close valve 100, thus preventing further reduction of train-pipe pressure. While supplemental reservoir pressure on .come the decreasing train-pipe pressure on diaphragm 17 and move the whole diaphragm system to the left, separator 29 will push open valve 33, permitting auxiliary reservoir pressure to flow through passage 26, port 34 to chamber 22, thence by passage 23 to brake cylinder 15. When brake cylinpressionby adjusting plug 119 and jamnut der pressure has so increased that the excess from space between 71 and 72 through pasdiaphragm 1.9 of the triple valve will over-.

while an upward movement of 114 pushes valve 123 oil its seat and admits pressure the parts are the same as in Fig. 10 and the g force due to brake cylinder pressure on dia phra rn 18 over that on diaphragm 17, equa s the difference of the force of supplemental reservoir pressure on diaphragm 19 over that of train pipe pressure on diaphragm 17, the diaphragm system will return to the right hand and allow valve 33 to close and prevent further increase of brake cylinder pressure. If it is desired to further increase the braking pressure, brake handle 78 is turned a little farther away from running position and the process before described is repeated successively at the pleasure of the operator, until brake handle has reached position of full equalized pressure, when train-pipe, brake cylinder and auxiliary reservoir pressures become equal and no further increase of brake cylinder pressure is obtainable.

For service application at high speeds, the operation is the same as for ordinary speeds, except that the handle 62 being in the position shown in Fig. 3,.the fluid pressure acts only on dia hragm 72, while space between 71 and 72 is open to the atmosphere at a, producing a higher running train pipe pres sure.

If pressure leaks'from the brake cylinder, the decrease in the excess force, due to brake cylinder pressure, on diaphragm 18 over that on dia hragm 17, will enable force of supplementa reservoir pressure to overcome the combined forces of train-pipe and brake cylinder pressures and againopen valve 33 to recharge brake cylinder, as previously set forth. If auxiliary reservoir in recharging brake cylinder, decreases in pressure below tram-pipe pressure, auxiliary reservoir is in.

turn replenished from the train-pipe through check valve 25. The decrease in train pipe pressure caused, by its recharging auxiliary reservoir, permits pressure in chamber 98 to overcome train-pipe pressure in space to the right of piston 102 and move piston 102 to the'right to open valve 103, and possibly valve 104, if dlflerence is great enough, ad mitting pressure from main reservoir to trainpipe until train-pipe pressure has again reached a value sufficient to balance pressure in chamber 98, move piston 102 and allow valve 103 or valves 1.03 and 104 to close.

'To make a partial release of the brakes, the

handle 78 is moved back toward running position a distance depending on the reduction in braking pressure desired. Cam 80 presses spring abutment 83 to the right hand, compressing spring 84, thereby increasing the force exerted by the springs on diaphragms 71 and 72, overcoming the force on diaphragms due to pressure from chamber 98 and diaphragms 71 and 72 move to the right pushing open valve 77' and admitting pressure from main reservoir to space 7 4 (and also,

' if system is running under the lower pressure,

.to space between 71 and 72). and chamber 98 viously described.

until equilibrium is again established, when valve 77 will close, preventing further in- The increased pressure in chamber 98 operates in the same manner as previously described. The increased pressure thus obtained in trainpipe, acts on diaphragm 17 along with the existing force of brake cylinder ressure on diaphragm 18 over that on diap iragnr 17 to overcome supplemental reservoir pressure on diaphragm 19 and push diaphragm system to the right, separator 30 will push open valve 31 and allow brake cylinder pressure to escape to chamber 24 and thence to atmosphere through ort 24*. When brake cylinder pressure as reduced until we again have a balance between the new train-pipe and brake cylinder pressures on one side and supplemental reservoir )ressure onthe other, valve 31 is allowed to o ose and prevent further escapeof brake cylinder pressure.

If train-pipe pressure increases during a partial release of the brakes to a point above auxiliary reservoir pressure, auxiliary reservoir will be recharged in the manner pre- To niakea total and quick release of the vbrakes,'liandle78 is moved to release position,

bringing 'port 49 in valve 4 7-. over port 56 in valve seat and port 50 in valve-47 over port '57 in valve seat, thus establishing direct connection between Ina-in reservoir and trainpipe; pressure also-fiowsfroin main reservoir to train-pipe through valves 1031 and 1.04, the

same as during a partial release. Brake handle remains in release position until trainpipe is charged to full running pressure, when handle should be turned to running position.

The operationof the triple valve when a full release is made is the same as during a partial release, except that valve 31 does not close until cylinder is completely exhausted to atmos here.

To ma e an emergency ap lication of the brakes, brake handle is-move quickly to the extreme limit of its motion, called emergency position, thus opening train-pipe direct to atmosphere through ports 56, 50, 49 and 58, while port 52 is opposite groove 66, establishing communication between equalizing chamber 98 and train- )ipe and producinga sudden application of the brakes throughout the train in the usual manner.

Due to the sudden decrease in, train pipe pressure, the diaphragm system, in'Fig. 2, moves to the left with such force as to unseat valve 42 against spring 45, when the remaining pressure in train-pipe lifts valve 43 and flows into chamber 22 and thence to brake c linder at the same time pressure flows s owly from auxiliary reservoir to brake cylinder through valve 33 I which is held open. When brake cylinder pressure and tra n-pipe pressure are about equal, valve 35 is lifted by the brake cylinder pressure and the auxiliary reservoir pressure against trainipe pressure, thus opening a large port etween brake cylinder and auxiliary reservoir and ahnost instantly char 'g .en

brake cylinder to its full pressure; release of brakes takes place, train-pi e pressure restores valve 35 to its seat'by t e' pressure on small piston 37. It *isimportant that valve 35' remain closed during an emer--' gency application of the brakes, until sufficient pressure has pipe to the brake cy der to cause the next triple valve in vthe train' to move "to emergency position. If valve 35 should open rematurely, the sudden flow of pressure horn auxihary reservoir to brake cylinder, would materially check the-flow of pressure from train-pipe to brake cylinder and might prevent the triple valves in the remainder of the train from going to emergency position. When the emergency application is made at the high pressure adapted for high speeds,-

it is necessary to reduce brake cylinder pressure as the train reduces in speed and comes to rest, or the wheels will slide on the rails.

When the emergency application is made,-

' hook on spring 81 catches on projection 82 main reservoir to space 12 an thus'efiectlng an increase in tlfllIl-plpe pres-- and ower is stored in the spring. As soon as t e emergency a phcatron'ls made, the engineer releases t e brake handle and spring 81 returns it to the speed rea leasing position; port 52 1s now over ort 60' and s ace 98 thereby connected wit s ace 124 o the governor, Fig. 10. Centri gal governor 112 is rotating at a speed roportional to the speed of the train an exerts a downward pull on diaphr m'11.4; this pull is aided by .the pressure 0 the. fluid re mammg in equalizing chamber 98, because chamber 98 and space 124 are connected by pipe 8, ports 65,63, 60, 52, .53 and 59,-and' plpe 9, and opposed bl); spring 118. As train reduces in speed, t ,e pull of governor 112, on diaphragm 114 decreases; When spring 118 overcomes the. opposing forces and moves diaphragm "114 upward, it will unseat valve 123 and admit gre'ssure from chamber'98,

sure and a graduated release of brake cylmder pressure in the manner previously described. This operation goes on continuously until train comes to rest.

In case a article of foreign matter becomes lodged between valve 123and its reventing the valve from closing or seat, p partia ly closing when spring 118 is overcome by governor 112 andincreas'ed pressure in 124 in order to check a too rapid flow of pressure into chamber 98, pressure in space 124 with the'help of governor 112 will overcom spring 118-to a suflicient extent to valve 125 from its seat and relieve pressure in space 124 to the required extent.

The value of thp coeflicient of frict on beassed from. the train-.

tween a cast-iron brake shoe anda steel tired car wheel is expressed approximately by the formula a a I .32 v f1+.o35S in which f equals" coefiic'ient of friction and S equals speed of' train in miles per hour;

The coefli'clent of .friction between car wheels andxtrack rails is practically a constant,-so long as there :isno sliding between them. Let 1 equal radius of gyration of governor 1 12 let 1: equal velocity of the center of gyrae tionof governor 112; then centrifugal force egrerted by governor 112 is proportional to y and since '0 is proportional to .r-X 8, contrifugal force'is proportional to I Q QT.

Let 0 equal the angle between axis of r0.- tation'of governor 112 and a line drawn through center of gyration and the upper hmge joint of governor. Then the downs r ct na'. LetL equal the distance from center of gyration to upper joint of governor, thenso downward pull of governor is proportional to v By-the use of spring 111, radius of. gyration r increases, while speed s of train in.

creases and R decreases while s decreases. Since 'L is a practically constant quantity, the decrease in r as 8 decreases checks a too rapid change in the value of the pull of governor 1-12. By properly proportioning spring 111 and governor 1.12, we can very nearly approach the ideal variation of train-- prpe. pressure so as to secure a brake cylinder pressure inversely proportional to the coefiicient of frictionf etween brake shoes and Wheels, and the maximum retarding eifect without the risk of slidin the wheels.

If it is desired to retard the action of valve 3.5, a suitable spring may be'plaeed to'the to check valve 25 in passage 26, said passage r in the cutaway portion opening at one end emental reservoir 16 is kept con-' 90 ward pull of the governor is proportional to to space and at the other end to supple "mental reservoir 16, said check valve in said the same manner'as descri ed when cutaway portion'permitting pressure to flow from space 20 to su plemental reservoir but preventing flow int e reverse'direction.

\ If brake handleis placed in running position before train-pipe pressure has. increased to full running pressure, or if pressure leaks from trainipe due to any'cause, train-pipe pressure w e restored b the feed valve in pressure leaked from brake cylinder. Q It will be readily seen that I may use flexible diaphragms in place of the pistons shown in Fig. 9 to operate the feed valves and the discharge valve without departing from the invention.

Having described my invention, I claim -1 In a fluid pressure brake system, the

combination of a train-pipe, a brake cylinder,

an auxiliary reservoir and a valve controlling a large port between the brake cylinder and auxiliary reservoir, said valve being subjected on one side to combined brake cylinder and auxiliary reservoir pressures and on the other side to train-pipe pressure.

2. In a fluid pressure brake system containing a train-pipe, a brake cylinder and an taining a train-pipe, an auxiliary reservoir,

a brake cylinder, a triple valve, and means for admitting .trainpipe pressure to brake cylinder in emergency applications of' the brakes, and a valve subjected on opposite sides to brake cylinder and train pipe pressure and havinga large intermediate port.

.4. In a fluid pressure brake system con taining a train-pipe, an auxiliary reservoir, a brake cylinder, a triple valve and means for admitting train-pipe pressure to the brake 'cylinder in emergency ap lications of the brakes, and a valve subjecte on opposite sides to brake cylinder and train pipe pressure and having a large intermediate port. i 5. In a fluid pressure brake system containing a brake cylinder, an auxiliary reservoir, a trainipe, a triple valve designed to secure a gra uated release of'brake cylinder pressure when train-pipe pressure is in creased to a correspon ing degree, and automatic means controlled by the speed of the train for gradually increasing train-pipe pressure as the speed of the tram decreases.

6. In a fluid pressure brake system, the combination of a brake cylinder, a tri le valve, a train-pipe and means controlled y the speed of the train for gradually increasing the pressure in the train-pipe as the speed of the train decreases.

.7. In a-fluid pressure brake system, an engineers valve rovided with means for returning its hand e to partial release position after it has been manually moved to emerency. osition, in combination with means or gas ually automatically increasing trainpipe "pressure as the speed of the train decreases.

8. In a fluid pressure brake system, an engineers valve rovided with means for returning its hand e to partial release position after it has been manually moved to emerency position, in combinationwith means For gra ually automatically increasing trainpipe pressure as the s eed of the train decreases, a brake cylin er and a triple valve adapted to reduce brake cylinder pressure as train-pipe pressure increases.

9. In a fluid combination of a rake cylinder, an auxiliary reservoir, a train-pipe, a triple valve adapted to reduce brake cylinder pressure as trainpipe pressure is fractionally increased, means operative automatically when an emergency application of the brakes is made and actuated by a part of the train whose motion relative to that of the train itself, depends ilpon the speed of the train, for gradually inspeed of the train decreases.

10. Ina fluid pressure brake system, the combination of a brake cylinder, an auxiliary to reduce brake cylinder pressure as trainmain reservoir, a valve controlling a port from the main reservoir to the train-pipe "and centriiu al mechanism actuated in accordance Wit the speed of the train to open said valve as the speed decreases.

11. In a fluid ressure brake system, the combination of a hrake cylinder, an auxiliary reservoir, a train-pipe, a triple valve adapted to reduce brake cylinder pressure as trainpipe pressure is fractionally increased, a main'reservoir, a valve controlling a port from the main reservoir to the train-pipe, a shaft rotating in roportion to the rotation of the axles of t e train and mechanism actuated by said shaft to open said valve for successivemtermittent intervals as the speed of the train decreases.

12. In a fluid pressure brake system, means whereby gra ual increases of pressure in the-train-pipe will effect corresponding decreases of pressure in the brake cylinder, in combination with a train-pipe, an engineers valve and means for automatically charging the trainipe after emergency applications to a gra ually increasing pressure varylng in proportion to the decrease 01' speed of the tram.

ressure brake system, the

creasing the pressure in the train-pipe as the Y reservoir, a train-pipe, a triple valve adapted pipe pressure is fractionally increased, a'

13. In a fluid pr essure brake system, the combination of a train-plpe and an engi- I neers valve, the lattercomprising a valve acted upon in one direction by sprlng tension and in: the other by fluid pressure, said -valve controlling the escape of said fluid pressure, a train-pipe feeding and discharge lvalvealso control sure, and means whereby the said spring fjhandle of'the engineers valve.

14. In :a fluid pressure brake system Zingv an auxiliary reservoir, a train-pipe, a brake cylinder: and a triple valve in which ed by the same fluid prestension can be altered by a'movement of the havtrain-pipe pressure and brake cylinder pres- I i sure cooperate in opposing a practically con- 'stant force, means whereby a reduction 1n train-pipe pressure will cause a valve to'be opened and held open'to admit pressure to brake cylinder from auxiliary reservoir until brake cylinder pressure has increased suffi-t ciently' to compensate for the decrease in train-pipe pressure in opposing said practically'const'ant force. 15. In a fluid pressure brake system having an aux1liary* reservoir, a train-pipe, a

brake cylinder and a'triple valve in which train-pipe pressure and brake cylinder pressure cooperate in opposing a practically constant force, means whereby an increase in train-pipe pressure will cause a-.valve to be opened and held open between brake cylinder and atmosphere until the resulting deing said practically constant force.

1' fsures cooperate in opgp stant force,

1 creasein brake cylinder pressure has offset the increase in train-pipe pressure in oppos- I 16., In a fluid pressure brake system havting-a brake jcy1inder, .an auxiliary reservoir, a: train-pipe, and1a triple valve in which train-pipe pressure and rake cylinder pressing a practicallyconmeans w ereby aleakage from,

-. or decreasein brake cylinder pressure'while trainpipe pressure remains unchanged, will cause a'va'lve to be opened and held open to admit pressure to brake cylinder from auxillary reservoir, until brake cylinder pressure has increased to the pressure obtaining before leakage occurred. 1

17. In a fluid pressure brake system containing a brake cylinder, an auxiliary reser voir, a triple valve and an engineers valve PIOVIdGd Wlth an equahzlng (llscharge valve and an equalizing 'feed valve, means controlled by the brake handle for varying the pressure in the equalizing chamber of said equalizing discharge valve and said equalizing feed valve and automatic means for maintaining any pressure in said equalizing chamber determined by a movement of the brake handle.

18. In a fluid pressure brake system, the combination of a brake cylinder, an auxiliary reservoir, a train-pipe, and a triple valve in which brake cylinder'pressure cooperates with train-pipe pressure In opposition to a practically constant force, means whereby an excess of combined train-pipe and brake cylinder pressures over said. constant force will move the parts of the triple. valve to release position, an excess of said constant force over combined train-pipe and brake cylinder pressures will move the parts of the triple valve to service position and an equality'between combined train-pipe and brake cylinder pressures, and the said constant force will move the parts of the triple valve to lap-position, an engineers valve adapted. 

